SONOSAX SX-VT Quick_Start - Manual (Page 4)

SONOSAX SX-ST RECORDER Quick Start Guide Page 4 of 26
1.1 A/D CONVERTER
The 8 ways high quality Analogue to Digital converter is located on the upper half of the Digital module. Its
sampling frequencies range from 44,1kHz up to 192 kHz with a resolution of 24bits. The overall dynamic
range reaches 120dB.
Each channel is equipped with a Limiter to protect the converter against eventual "clipping".
The 8 digital channels – 4x AES/EBU pairs – are available on the 25 pin Sub-D connector [DIGITAL I/O] on
the rear panel of the mixing console. These four digital outputs are transformer balanced and comply with the
AES31 standard. The configuration of these digital outputs is:
AES 1 = channels 1 & 2 AES 2 = channels 3 & 4
AES 3 = channels 5 & 6 AES 4 = channels 7 & 8
Please refer to the addendum for the wiring diagram of the 25 pin Sub-D connector.
1.1.1 Source selector [IN 1 MIX] to [IN 8 MIX]
The eight A/D Converters receive either the direct output of the first 8 input channels or the 8 master outputs
of the Groups 1 to 8. The switches [IN 1 MIX] to [IN 8 MIX] individually select for each digital channel which of
the source is sent to the corresponding A/D converter:
- Position [IN]: the direct output of the corresponding Input module is sent to the A/D Converter. It is
the same modulation as outputted at the [LINE OUT 1-8] connector. Thus, it depends
on the internal selection Pre EQ – Post EQ – Post Fader.
- Position [MIX]: the modulation of the corresponding Group is sent of the A/D Converter.
- Centre Position: The A/D Converter is powered off, thus reducing the overall power consumption of the
console. The A/D Converters are always powered per pair; therefore both switches of
the same pair must be in centre position to power off the converter.
Please note that powering the ADC on or off generates an audible noise.
1.1.2 Red led indicator [ L/O ]
The red Led [L/O] located above each source selector lights on either to indicate the Limiter activity [L] (when
the modulation reaches the Threshold of the limiter) or when the modulation reaches the clipping level at
0dBFS [O] (O= overflow).
NOTE: as soon as one of the channel of an ADC reaches the clipping level, both leds will light On to
indicate the Overflow
1.1.3 Protection Limiter's [ LIMITERS ]
Each of the eight channels of the digital module is equipped with an individual limiter to prevent the ADCs from
eventual clipping (or overflow). To provide with an efficient protection, the Limiters have a very fast attack time
of half a period.
The [LIMITERS] switch engages or disengages the eight limiters simultaneously.
The Limiter's Threshold is factory set at -3dBFS; its "compression" ratio is approx 15:1
1.1.4 Sampling frequencies
The A/D Converters have a fixed resolution of 24bits; the sampling frequencies stage from 44,1 up to 192kHz,
and is determined by two switches:
- The upper switch selects one of the two fundamentals frequencies; 44,1KHz or 48KHz
- The lower switch selects a multiple of these fundamentals: 44,1 – 88,2 – 176kHz or 48 – 96 – 192kHz
NOTE: The 0.1% Pull Up / Pull Down functionality, commonly used in NTSC domain, is only possible
when the internal recorder is installed.